Toilet Flush Valve With Reducing Cross Section Valve Seat

ABSTRACT

A canister flush valve is disclosed with a valve seat modified to accommodate a greater initial surge of flow, without distorting flushing performance. There is a mounting at the bottom of a toilet tank that links to an outlet hole from the tank and forms a valve seat. A passageway through the mounting tapers in an arcuate manner below the valve seat. There is also a guide support structure in the passageway, preferably centered. The guide support structure also has a tapered leg.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority based on U.S. provisional application61/043,817 which was filed Apr. 10, 2008, and also U.S. Ser. No.12/416,179 filed Apr. 1, 2009.

This application also claims priority on U.S. application Ser. No.12/184,740 filed on Aug. 1, 2008, and its parent U.S. application Ser.No. 11/268,151 filed on Nov. 7, 2005, both of which are incorporatedherein by reference as if fully set forth herein.

STATEMENT OF FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not applicable.

BACKGROUND OF THE INVENTION

The present invention relates to flush valves that control the flow ofwater from toilet tanks to toilet bowls. More particularly, theinvention relates to a tank valve seat mountable to a toilet tank andpreferably used with canister type flush valves.

Many systems for controlling the flow of toilet tank water to a toiletbowl are known. Such systems have a water inlet valve connected to thetank that is typically controlled by a float that reacts to the tankwater level. Depressing a trip lever or other actuator moves a flushvalve at the tank outlet so that water can empty from the tank into thebowl. As the tank water drains, an inlet valve float drops with thewater level in the tank, thereby triggering inlet water flow to refillthe tank. After sufficient tank water leaves the tank, the flush valvecloses so that the water level in the tank can be re-established. As thetank refills after the outlet valve has closed, the supply valve floatrises with the water and eventually closes the supply valve to shut offthe water supply.

A variety of flush valves have been devised for controlling the flow ofwater from the tank to the bowl. One of the most common is the flappertype flush valve. Flapper flush valves have a pivotal yoke that supportsa large diameter stopper that seals off the tank outlet until the triplever is actuated to start a flush cycle. The large stopper is filledwith air that slows the reseating of the stopper until sufficient waterhas been drained from the tank. On occasion, some such valves havedifficulty in completely closing off outlet flow if the flapper doesn'tdrop onto the valve seat exactly right.

Another type of flush valve has a dedicated float that moves straightvertically upwards once tripped, and then straight vertically downward.See e.g. U.S. Pat. Nos. 5,329,647, 5,896,593, 6,715,162, and 6,728,976.

A particularly preferred type of flush valve that works in this manneris the canister flush valve shown in U.S. patent application publication2007/0101485, which is hereby incorporated by reference as if fully setforth herein. However, this type of canister design, when used with itsshown valve seat, presents a number of design constraints.

For example, to achieve sufficient initial flow one may have to increasethe diameter of the entry to the bowl's rear extension to a point wherenon-standard fittings are required, and/or aesthetics are affected.Moreover, the flow characteristics may be such as to limit certain waterusage efficiencies that must be compensated for otherwise.

One complicating factor is that in order to insure vertical movement ofthe valve body, a guide is positioned on the valve seat. As this istypically at the center of the flow passage through the seat, the guideitself can impede flow and complicate design revisions. While U.S. Pat.No. 5,926,861 proposes to have the guide for the canister be at theperiphery of the seat, it requires a relatively complex and expensivestructure to implement that proposal.

In light of the above, improvements are needed to address theseconcerns.

SUMMARY OF THE INVENTION

The present invention covers in one aspect a flush valve for controllinga flow of water out through a hole in a wall of a toilet tank. The flushvalve has a mounting having a lower end suitable for facilitatinginstallation of the mounting adjacent the hole, an upper end in a formof a valve seat, and a through passage extending down from the valveseat. It also has a guide portion mounted in the through passage andextending upward there from.

There is also a valve body positionable over the valve seat so as to besuitable to inhibit water flow through the mounting when in a firstposition where the valve body is positioned on the valve seat, and so asto be suitable to permit water flow through the mounting when the valvebody is in a second position where the valve body is not positioned onthe valve seat. In accordance with the present invention the throughpassage tapers below the valve seat.

In preferred forms the through passage arcuately narrows below the valveseat from a diameter above 2.9 inches to a diameter below 2.3 inches,more preferably below 2.1 inches, the valve body is a canister typevalve body, the guide portion has a lower leg structure that tapersarcuately below the valve seat, and the mounting has external threadsproximate a lower end of the mounting so as to facilitate installationof the mounting through the tank hole. Alternatively, when a one-piecestyle toilet is involved with a blind attachment hole, instead ofthreading the lower end of the structure one can use a bayonet styleattachment system like that of U.S. Pat. No. 4,433,446.

It will be appreciated that the enlarged valve seat and correspondinglylarge canister valve produces a large discharge flow rate of water toenter as soon as the canister valve is lifted off the valve seat. Thetapering of the passageway below the valve seat (and the correspondingtapering of the guide portion) then permit the flow to be smoothlytransitioned to the desired size with no impedance to the developed flowrate.

In another aspect the invention provides a mounting useful as part ofsuch a flush valve. That mounting may have a body in the form of asleeve and have a lower end suitable for facilitating installation ofthe body adjacent a tank wall outlet hole. The mounting also has anupper end in a form of a valve seat, a through passage extending downfrom the valve seat, and a guide post mounted in the through passage andextending upward there from. The through passage tapers below the valveseat.

It should be noted that the guide post can be centered along the centerline of the canister valve body for optimal guiding. This is also a costeffective way of achieving the guiding. However, adequate flow can occurpast the guide portion, even in connection with low flush toilets.

In another aspect the invention provides a toilet (with tank and bowl),where the above flush valve controls outflow from the tank to the bowl.

Hence, the present invention improves the performance of conventional,high performance, canister valves so as to permit an uncompromiseddischarge flow rate of water to quickly pass into the toilet onceflushing has started. This is achieved at relatively low cost, and in amanner that does not require the bowl rear extension to be widened toaccommodate the greater flow.

These and other advantages of the invention will be apparent from thedetailed description and drawings. What follows are one or morepreferred embodiments of the present invention. To assess the full scopeof the invention the claims should be looked to as the preferredembodiment(s) are not intended as the only embodiment(s) within thescope of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a sectional view depicting a flush valve of the presentinvention installed in a toilet tank of the present invention;

FIG. 2 is a top plan view of the FIG. 1, with the tank cover removed;

FIG. 3 is a perspective view of the FIG. 1 flush valve;

FIG. 4 is an exploded perspective view of the FIG. 2 flush valve;

FIG. 5 is a view similar to FIG. 4, but showing the parts from adifferent angle;

FIG. 6 is a sectional view taken along line 6-6 of FIG. 3;

FIG. 7 is a sectional view taken along line 7-7 of FIG. 3;

FIG. 8 is an enlarged detail view per arc 8-8 of FIG. 6;

FIG. 9 is an enlarged top perspective view of a preferred mounting ofthe present invention;

FIG. 10 is a bottom perspective view of the FIG. 9 mounting; and

FIG. 11 is a view similar to FIG. 6, but showing the canister valve bodyraised to a second position off the valve seat.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring first to FIGS. 1 and 2, a toilet 10 is shown that includes awater tank 12 and a bowl 14 (partially shown in hidden lines). The tank12 may be coupled to the bowl 14 using a bracket like that of U.S. Pat.No. 6,728,976.

The tank 12 includes a cover 16 and a generally horizontal bottom wall18 with an outlet opening 20 that leads to a channel in an upper rim(not shown) of the bowl 14. Mounted inside the tank is the typical watersupply pipe 22 with a float 24 operated supply valve 26 for controllingthe flow of supply water 28 into the tank 12. In this regard, when thefloat drops (as water has exited the tank), water is supplied to thetank. Once the float follows the water back up far enough, the supplywater automatically turns off.

A flush valve assembly 30 in accordance with the present invention ismounted inside the tank 12 over the outlet opening 20 to control theflow of water 28 out from the tank 12 to the bowl 14 during a flushcycle. A trip lever assembly 31 is coupled to the tank 12 and to aportion of the flush valve assembly 30 and can be triggered to initiatea flush cycle.

With additional reference to FIGS. 3-5, the flush valve assembly 30 ismounted vertically upright in the tank 12 proximate the bottom wall 18.The flush valve assembly 30 primarily includes a mounting 32 and a valvebody 34 incorporating a seal 36 that moves relative to the mounting 32generally along a central axis 38 (shown in FIGS. 2 and 3). The mounting32 and the valve body 34 are preferably constructed of a non-corrosive,chemical resistant material, such as a suitable plastic. The seal 36 canbe made of a flexible material, for example a suitable elastomer, suchas vinyl, EPDM rubber, or silicon, which has particularly goodchemical/corrosion resistance properties. However, one skilled in theart will appreciate the variety of materials suitable for the mounting32, valve body 34, and seal 36.

The mounting 32 is coupled to the tank 12 by a retaining nut 39 thatthreads onto exterior threads 40 formed proximate the lower portion 42of the mounting 32 that extends through the tank outlet opening 20. Anannular flange 44 extends radially from the mounting 32 to sandwich agasket 46 between the bottom wall 18 of the tank 12 and the flange 44(best shown in FIG. 1). This gasket 46 prevents water 28 from leakingfrom the tank 12 and, for instance, onto the floor of a bathroom.

In one alternate example configuration not shown, the lower portion 42of the mounting 32 can have three prongs that extend through atrilobular opening and engage the tank 12. This connection is similar tothat disclosed in U.S. Pat. No. 4,433,446, which is assigned to theassignee of the present invention, and the disclosure of which,particularly FIGS. 2-6 and the related description, is herebyincorporated by reference.

With additional reference to FIGS. 6-11, the mounting 32 defines apassageway 48 that extends between a valve seat 50 at one end and avalve outlet 52 at the opposite end. The passageway 48 defines asubstantially arcuate surface 54 that tapers down from the valve seat 50toward the valve outlet 52, as best shown in FIG. 6. The arcuate surface54 may be smooth to minimize impediment to the flow of water 28.Additionally, the arcuate surface 54 is preferably contoured to mimicthe natural flow of water 28 so as to maximize the flow rate of thewater 28 from the tank 12 to the bowl 14. The passageway 48 includes alinear portion 56 proximate the valve outlet 52; however, the passageway48 may be entirely arcuate from the valve seat 50 to the valve outlet52.

In the preferred example embodiment, the valve seat 50 and the valveoutlet 52 are preferably concentric with respect to a central axis 38.The valve seat 50 is substantially circular and has a valve seatdiameter 58 that is greater than a valve outlet diameter 60 (shown inFIGS. 9 and 10). The valve outlet 52 is also substantially circular.

In the example embodiment, the valve seat diameter 58 is approximatelythree inches to allow for a sufficient amount of water 28 to flow bothduring the initial inrush of a flush cycle and during the balance of theflush cycle. The passageway 48 reduces the larger valve seat diameter 58to a valve outlet diameter 60 of approximately two inches proximate thevalve outlet 52. As a result, the passageway 48 funnels or directs thewater 28 toward the bowl 14, providing sufficient bowl 14 cleaning andwaste removal water 28 during a flush cycle, and to permit coupling themounting 32 to more traditional components and fixtures.

The passageway 48 may take on a variety of arcuate surfaceconfigurations of reducing cross section, with each having a goal ofefficiently transferring water 28 from the tank 12 to the bowl 14 duringa flush cycle. The tapered passageway 48 has the added benefit of makingthe mounting 32 compatible with standard bowls and other couplingcomponents, while allowing the enhanced flow of water 28.

The mounting 32 includes a series of supports 62 in the form ofarcuately tapered legs that extend inward from the passageway 48 andconverge proximate the central axis 38 where they define an opening 64.The supports 62 taper below the valve seat 50 toward the valve outlet 52to maximize the flow of water 28 through the passageway 48. The opening64 is configured to receive a guide portion 66 in the form of a post.The guide portion 66 has a pair of legs 68 formed proximate a lower end70 that selectively lock into the opening 64 to prevent axial movementof the guide portion 66.

The guide portion 66 also includes upwardly extending tapered gussets 72that terminate in a hollow upper end 74 that is configured to receive arefill nozzle 76 and stop washer 78 that captures the valve body 34 tothe guide portion 66. During a flush cycle, the refill nozzle 76receives water 28 from the supply valve 26 via tube 80. The refillnozzle 76 allows water 28 to fill a portion of the valve body 34 andtank 12 during a flush cycle to influence the duration of the flushcycle and to restore the bowl water to an initial level.

The substantially cup-shaped valve body 34 is a type of float that isopen to the ambient at a top 35 and includes an exterior wall 85 and aninterior tube 86 that generally rides along the guide portion 66 duringa flush cycle. The interior tube 86 is substantially conical and taperstoward an upper rim 88 of the tube 86. The conical configuration of theinterior tube 86 acts to center the valve body 34 with respect to themounting 32 as the valve body 34 sinks from the raised position to thelowered position. Should water 28 breach the upper rim 82 of the valvebody 34, the water 28 begins to fill a circular pocket 84 formed betweenthe interior tube 86 and the exterior wall 85. The water 28 drainsthrough openings 73 first and then climbs to upper rim 88 of theinterior tube 86 if the incoming overflow rate is high enough. Note alsogussets 72.

The trip lever assembly 31 includes a chain 98 that is hooked betweenhole 100 formed in a side tab 102 of the valve body 34 and the trip arm104, as a result, actuating the trip lever assembly 31 moves the valvebody 34 from the lowered position (shown in FIG. 6) toward the raisedposition (shown in FIG. 11).

With specific reference to FIGS. 6-8, when the valve body 34 is in thelowered position, the seal 36 prevents water 28 from leaking from thetank 12 to the bowl 14 proximate a perimeter 96 of the mounting 32. Thetypically disk-shaped seal 36 is secured in an annular groove 90 formedproximate the lower end 92 of the valve body 34. In the preferredexample embodiment, the seal 36 at least partially engages a ridge 94that extends upward from the valve seat 50 proximate the perimeter 96 ofthe valve seat 50 (shown best in FIG. 8) to help establish a watertightseal between the seal 36 and the valve seat 50. Furthermore, an annularseal-backing flange 106 is spaced apart from the seal 36 and enhancesthe operation and sealing of the seal 36. Additionally, a series ofslots 108 are formed in the seal-backing flange 106 to enhance theoperation of the valve body 34 during a flush cycle. One skilled in theart will appreciate the variety of configurations available to retainthe seal 36 to the valve body 34.

The bleed openings 73, seal-backing flange 106, slots 108, and otheradditional structures are discussed in U.S. patent application number2007/0101485 that is assigned to the assignee of the present invention,which is hereby incorporated by reference as if fully set forth herein.

Prior to a flush cycle the flush valve is in the rest position shown inFIGS. 1, 3, 6, and 7, with the valve body 34 and seal 36 seated on thevalve seat 50 and a “full” tank 12 of water 28 available. Actuating thetrip lever assembly 31 pulls the valve body 34 upwardly a sufficientdistance to cause the seal 36 to unseat from the valve seat 50. When theseal 36 is initially unseated from the valve seat 50, the flared valveseat 50 portion of the passageway 48 allows the water 28 to flow intothe bowl 14 with an initial inrush equivalent to a valve of uniformdiameter of valve seat 50.

Through the buoyancy of the valve body 34, the valve body 34 is movedfurther toward the raised position shown in FIG. 11. The water 28 in thetank 12 continues to flow through the mounting 32 along the arcuatesurface 54 of the passageway 48 that mimics the natural flow of water 28toward the bowl 14. Additionally, the tapered supports 62 minimize water28 flow resistance in the passageway 48. Water 28 and waste in the bowl14 are evacuated to plumbing waste lines in the usual manner through atrap (not shown). The valve body 34 travels down the guide portion 66until the seal 36 again seats in the valve seat 50 in conjunction withan engineered bleed rate controlled by openings 73. The flush cyclecompletes after the tank 12 is refilled with water 28 sufficient to tripthe supply valve 26.

It should be appreciated that preferred embodiments of the inventionhave been described above. However, many modifications and variations tothe preferred embodiments will be apparent to those skilled in the art,which will be within the spirit and scope of the invention. Therefore,the invention should not be limited to the described embodiments. Toascertain the full scope of the invention, the following claims shouldbe referenced.

INDUSTRIAL APPLICABILITY

The present invention provides improved valves for use in controllingoutflow of water from a toilet tank to a toilet bowl, and toilets whichincorporate these valves.

1. A flush valve for controlling a flow of water out through a hole in awall of a toilet tank, the flush valve comprising: a mounting having alower end suitable for facilitating installation of the mountingadjacent the hole, a valve seat, and a through passage extending downfrom the valve seat; and a valve body positionable over the valve seatso as to be suitable to inhibit water flow through the mounting when ina first position, and so as to be suitable to permit water flow throughthe mounting when the valve body is in a second position; wherein thethrough passage arcuately narrows below the valve seat.